of springfield



Jan. 13, 192

1 523 030 c. A. MAYER ET'AL v MAGNETO Q 4 Filed, July 28, 1921 a 7-! f 6 I n v Q I I 5 I 3\ 6O 30 M 1 I 12 4% Fig. 3

INVENTORS C.AUGU5T MAYER & ADOLPH ROSNER T ORNEY Patented Jan. 13, 1925.

UNITED STATES PATENT OFFICE.

CARL AUGUST MAYER AND ADOLPH ROSNER, 0F SPRINGFIELD, MASSACHUSETTS, ASSIGNORS TO AMERICAN BOSCH MAGNETO CORPORATION, OF SPRINGFIELD, MASSACHUSETTS, A CORPORATION OF NEW YORK.

MAGNETO.

Application filed July 28,

To all whom it may concern:

Be it known that CARL AUcUs'r MAYER and ADOLPH RosNnR, citizens of the United States, residing at and whose post-oifice addresses are, respectively, 30 Arch Street, Springfield, and 4 Ventura Street, Springfield, in the county of Hampden and State of Massachusetts, have invented certain new and useful Improvements in Magnetos; and we do hereby declare the following to be a full, clear, and exact descrip tion of the invention, such as will enable others skilled in the art to which it apper tains to make and use the same.

The present invention relates to magnetos having relatively movable magnetic parts and a generating winding affected thereby, as well as a mechanical interrupter electrically connected in the circuit of the generating winding and having separable parts actuated by suitable actuating means.

In the manufacture of magnetos, many manufacturing variations enter into the final product. Very frequently these variations accumulate and produce too large a final Variation between certain parts, particularly in regard to the edge distance between the relatively movable magnetic parts, such as the armature and pole shoes of a magneto, as related to the separable contacts of the interrupter, at the time of their actuation when at their fully advanced position.

Furthermore, in operation there is wear of certain parts such as the cam of the interrupter mechanism, or the striking block of the interrupter lever, or the bushing at the interrupter pivot, or the contact points. Such variation in manufacture and wear in operation make it desirable for the best performance of the magneto to provide an adjustment for the edge distance, by which is meant the magnitude of the gap between the parting edges of the two relatively movable magnetic parts of the magneto at the instant of separation or actuation of the interruper contacts when the magneto is set to its position of maximum or full advance.

In accordance with one part of our invention, the edge distance adjustment comprises means for securing in adjusted position a member, specifically an abutment such as a stop pin, for determining the angular position of the interrupter cam in full advanced position. lVhether or not such means are 1921. Serial No. 488,232.

employed, our invention further comprehends means for securing the stop pin in a selected one of several positions, or for securing the stop pin in reversed position, so that the same means may be employed for operating the magneto with fixed or variable timing in either direction of rotation. Furthermore, the invention comprehends means for sealing the edge distance adjustment to prevent tampering that would defeat the purposes of the adjustment.

Referring to the attached drawings on which is shown an embodiment of the invention, in application to a magneto having stationary pole shoes and a rotary armature, as an example,

Fig. 1 is a view in elevation of an end portionof a magneto having the invention; Fig. 2 is a transverse sectional view taken on line 22 of Fig. 1 and showing one setting.

arrangement; Fig. 3 is a similar view show ing another setting arrangement; Fig. 4 is a fragmentary end view of the relatively movable magnetic parts in the relation of a setting; Fig. 5 is an end view of the interrupter housing with the end cap removed; Fig. 6 is a view in elevation of the cover plate; and Fig. 7 is a similar view of the adjustable plate and pin.

The present invention is embodied in a magneto comprising a base member 1, permanent magnets 2 and a gear housing 3 fastened to one end of the magneto, as shown in Fig. 1. To the gear housing is secured, in a suitable manner, a distributor plate a and an end plate 5, the latter having, as an integral part thereof, an interrupter housing portion 6. This portion is of annular form and has fitting within it a cam ring '7 which together with the member 6 forms the interrupter housing proper. The cam ring 7 is mounted in the member 6 in either the fixed or adjustable position, that is to say, in the former position, the ignition is not adjustable while in the latter it is, as will more clearly appear hereinafter. Fastened to the cam ring 7 is a timing ring 8 having a radially extending timing arm 9 to which may be suitably connected operating members which extend within easy reach of the operator of the vehicle whenever it is desired to advance or retard the ignition. Such connections, however, also may be connected, if desired, to automatic means operated by the engine for automatically advancing or retarding the ignition. Upon the end of the ring 7 is located a closure cap 10 of any suitable material, such as bakelite or the like, such cap being resiliently held in place by a suitable spring connected to a post 11 fastened to the end plate 5, in a known manner. The cap carries a binding post 12 by means of which the ground or short-circuiting lead may be connected to the interrupter mechanism within the interrupter housing.

Vvithin the magneto frame is rotatably supported a rotor 13 comprising a core 14, which is usually laminated, and core heads 15 and 16 carried at the ends of the core 14. Upon the core between the heads 15 and 16 are wound the generating windings of the magneto, such windings usually comprising primary and secondary windings. The rotor in general operates or rotates between two pole shoes 17 and 18 which are fastened to the magnets 2 by means of screws 19 and 20, all as is clearly shown in Fig. 4 of the drawings.

Referring now more particularly to Fig. 2 of the drawing, wherein the mechanism is shown assembled for clockwise rotation of the armature and the rotating parts of the mechanical interrupter, Figure 2 being a rear end view of the magneto, the cam ring 7 is shown as having a radial aperture 21 and an arc-shaped slot 22 into either one of which may extend a stop pin 23, the latter acting as a limit stop for the angular move ment of the ring 7 when such pin extends into the slot 22, or as an anchoring member for maintaining the position of the ring 7 when extending into the aperture 21. The end of the rotor shaft extends within the interrupter housing and has fastened to it a base plate 24 by means of an end screw 25. To this plate is fastened a block 26 by means of a screw 27, the block 26 being suitably insulated from the. base plate 24 and carrying a contact supporting screw 28 adjustably held in place by means of a lock nut 29, the screw 28 having, at one of its ends, an interrupter contact 30, a hexagonal head 31, made integral with the screw 28, being of utility for adjusting the screw and the contact 30 when desired. The base plate 24 also pivotally carries an interrupter lever 32 which has at one end thereof a movable interrupter contact 33 and at its other end a fibre striking block .34 adapted to cooperate with cams 35 and 36 fixed to the cam ring 7. A spring 37 is pivotally connected at one end to a post 38 fastened to the base plate 24 and bears at its other end the end of the pivot of the interrupter lever so as to maintain the lever upon its bearing. A spring 39, adapted to resist the deflection of the lever 32 by the cams 35 and 36 and to return the movable contact 33 against the relatively stationary contact 30,'is connected at one end to the lever 32 and at the other end to a post 40 fast with the base plate 24. The end plate 5 is fastened to the end of the magneto housing by means of screws 41 and 42 and the post 11, to the latter of which is fastened a spring which normally holds the end closure in place.

The stop pin 23, heretofore, was usually fastened to' the member 6. In the present invention, however, the pin 23 instead of being fastened to the member 6, is fastened to a removable arc-shape plate 43, which in turn is fastened to the housing member 6, between a rib 64 formed integral with the member 6 and the plate part 5, by means of screws 44 and 45, the plate 43 being provided with elongated countersunk recesses 46 and 47 for the reception of the heads of the screws 44 and 45, respectively. The plate also has elongated apertures 48 and 49 located so that the plate may be angularly moved or adjusted about the axis of the magneto and along the surface of the housing member 6 to the extent of the length of such elongated recesses and apertures, as is clearly shown in Fig. 2 of the drawing. hen the plate is adjusted, the screws are threaded home so as to bind and maintain the plate in fixed position. In view of the fact that the pin 23 is fixed to the plate 43, it will also partake of the angular movement or adjust-ment of the plate, and for this reason the housing memher 6 also is provided with an elongated aperture 50 to permit the pin 23 to move therein to the extent of the length of such aperture. As above stated, Fig. 2 shows the parts in the arrangement where the pin 23 extends into the slot 22 of the cam ring, whereby the cam ring may be angularly moved by means of the timing ring 8 and the timing arm 9 so as to cause either the shoulder 51 or 52 to abut against one or the other side of the pin 23, such movement permitting the advancing or retarding of the ignition to the extent of the length of the slot 22, and the position of the pin 23.

Due to the various manufacturing variations, mentioned above, if the pin 23 were secured in fixed position in the housing iember 6, it is obvious that when either the end 51 or 52 abutted against the pin 23, and also in view of 'thefact that the interrupter contacts are mounted upon a rotatable member fastened to the rotor 14, the fully advanced position of the cam ring 7 might be such that when the interrupter contacts 30 and 33 separated, the trailing ends 53 and 54 of the armature heads 15 and 16, respectively, would he at too little or too great a distance from the edges 55 it is found that the distance between the edges 53 and 54:, and 55 and 56, should be within three and a fraction millimeters or less at the instant when the interrupter contacts separate whereby the-most efiicient operation may be had. Such edge distanc'e is illustrated upon the drawing as the distance between the two parallel lines 68 and 69, the former passing through the ends 53 or 5et, and the latter through the edges 55 or56 of the pole shoes, as the. case may be, such distances being designated by the reference character E on'the drawing. It will be observed that the contacts will separate at the time when the fibre block 34; strikes upon and rides over the surfaces of the cams and 36, and the lever 32 is accordingly deflected. Therefore, if the edge distance between 53 and 55, or 54 and 56, is either too little or too great, the limit stop 23 may be adjusted angularly so that the abutting ends 51 or 52 of the cam ring 7 may contact with the pin 23 in a more advanced or retarded position. To accomplish this purpose, the pin 23 is made adjustable by adjusting the position of the plate 43. This adjustment is made when assembling the parts with the screws 41 and 12 in loosened position and the plate 43 angularly adjusted toproper limiting position and then the screws 41 and 412 are tightened so as to fix the plate in adjusted posit-ion, and hence the pin 23.

If, however, it be desired to operate the magneto in clockwise direction but with fixed ignition, the cam ring may be rotated or turned 180 from its position shown in Fig. 2, so as to bring the aperture 21 therein in registry with the aperture. 50,- and the plate l3 is then located into place with the pin 23 extending through such registering apertures. The plate 43, together with the pin 23, may then be adjusted to set the ring 7 in proper angular relation with the rotating parts so that the edge distance may be the desired amount at the instant of separation or actuation of the contacts 30 anc 33, the cams 35 and 36 elfecting such actuation atthat instant. It Will thus be apparent that if the edge distance be too great or too little at the instant of separation of the contacts 30 and 33, the plate 43 together with the pin 23 may be angularly adjusted in either direction within the limits of the slot 50, until the proper an gular relation of the parts is obtained, after which the platev is secured in place as heretofore and the securing screws sealed.

If, on the other hand, it is desired to operate the magneto in an anticlockwise direction and with adjustable ignition, the rotating parts of the interrupter mechanism are rearranged into a reverse position, such as is shown in Fig. 3 of the drawing, the same reference characters, however, being used to designate the same or corresponding parts. In. such arrangement, the cam ring 7 is rotated about 53 and 20 from the position shown thereof in Fig. 2 to that shown in Fig. 3, so that the s1ot22 registers with an elongated aperture 57 provided in the housing member 6 at about 18 and 20 from the aperture 50. The plate a3 is then reversed in position so as to insert the pin 23 through the aperture 57 and to, extend into the slot 22 of the cam ring. In fully advanced position, the end 52 of the ring 7 abuts against the pin 23. If, however, this position is inaccurate so that the edge distance be not that desired at the instant of separation of the contacts 30 and 33, the plate -il3 is angularly adjusted together with the pin 23 so that the end 52 of the cam ring will abut with the pin 23 at a more advanced or retarded position in accordance with the adjustment made.

If, however, it is desired to operate the magneto in anti-clockwise direction but with fixed ignition, the cam ring 'Tis ro tated so as to bring the aperture 21 into registry with an elongated aperture 58, and the plate 43 together with the pin 23 is placed upon the opposite side of the housing member 6from that shown in Fig. 2, and in between rib 65 formed integral with the member 6 and the plate part 5, so that the pin 23 will extend through the apertures 58 and 21, and thus maintain the ring 7 from angular movement. The aperture 58, being elongated, will permit the necessary adjustment of the pin 23 therein for adjusting or setting the cam ring 7 to the position where the edge distance between the edges 53 and 55 or 5a and 56 will be of proper value at the instant of actuation of the interrupter contacts. The housing member 6 is also provided with apertures for threading therein of binding screws 44 and 45. lVhenever the plate 43 is in either position on either side of the housing member 6, and in order to prevent entry of foreign matter into the interrupter housing, a cover plate 59 of arcuate form is interchangeably secured to the opposite side of the housing from that upon which the plate 43 may be secured at the time, so as to cover the aperture 58 or the apertures 50 and 57 as the case may be, such plate 59 being held secured in place by screws 60 and 61 capable of being threaded into the threaded apertures provided for the screws 44. and 45 when securing the plate 43 in position. The heads of the screws 60 and 61 rest in countersinks or recesses 62 and 63 formed in the cover plate 59, as is clearly shown in Figs. 2 and 3. The ribs 64 and 65 may be provided with index marks 66 located in alinement with the centers of the apertures 58 and 50, while the plate 43 may have an index mark 67 passing through the axis or center of the pin 23, as shown, in order to indicate the amount of adjust ment made.

After adjustment is made by the manufacturer at the time of assembling the magneto, the recesses a6 and 47, as well as the recesses 62 and 63 are filled with a suitable sealing material or compound in order to prevent ready access to the heads of the screws, thereby discouraging any attempt of a mechanic to make his adjustments of the position of the pin for setting the edge distance of the magneto.

Fig. 5 shows the various controlling apertures for determining the different adjustments or" the pin 23, the letter A designating the aperture which controls the edge distance setting for anti-clockwise rotation of the magneto when using adjustable ignition, the letters C and CF indicating the apertures which control the position of the pin for setting the edge distance for clockwise rotation when using adjustable and fixed ignition, respectively, and AF designates the controlling aperture for anti-clockwise rotation when using fixed ignition.

From the above, it will be apparent that the adjustment is readily made by a simple means which by reason of its being located on the outside of the interrupter housing is easily accessible to the manufacturer at thetime. of assembly of the magneto and setting the edge distance thereof, and is so arranged that the adjustable member may be selectively and reversibly located into different positions and on different sides of the housing for either clockwise or anticlockwise rotation of the rotor, as well as for adjust-able and fixed ignitions.

Having thus described our invention, what we claim is:

1. In a magneto,a mechanical interrupter, means for actuating the interrupter, a housing for the interrupter, and an adjustable plate secured in adjusted position on the housing, said plate having means coopera tive with the actuating means for setting the edge distance of the magneto.

2. Ina magneto, a mechanical interrupter, means for actuating the interrupter, a housing for the interrupter, and an adjustable plate secured in adjusted position on the housing, said pl'ate having a stop pin cooperative with said actuating means for setting the edge distance of the magneto.

3. In a magneto, a mechanical interrupter, means for actuating the interrupter, a housring for the interrupter, and an adjustable plate secured in adjusted position on the housing, said houslng having an aperture and said plate having a stop pin extending through said aperture in cooperation with V 4. In a magneto, a mechanic'al interrupter,

means for actuating the interrupter, a housing for the interrupter, and an adjustable plate secured in adjusted position on the housing, said housing having an elongated slot and said plate having a stop pin adjustably extending through said slot in cooperation with said actuating means for setting the edge distance of the magneto.

5. In a magneto, a mechanical interrupter, means for actuating the interrupter, a housing for the interrupter, and an adjustable plate secured in adjusted position on the housing, said housing having two elongated slots and said plate having a stop pin selectively and adjustably extending through either of said slots in cooperation with said actuating means for setting the edge distance of the magneto.

6. In a magneto, a mechanical interrupter, means for actuating the interrupter, a housing for the interrupter, and an adjustable plate selectively secured in either of two po sitions' on opposite sides of said housing, said housing having elongated slots in opposite sides thereof and said plate having means adj ustably and selectively extending through any of said slots in cooperation With said actuating means for setting the edge distance of the magneto in either direction of rotation.

7 In a magneto, a mechanical interrupter, means for actuating the interrupter, a housing for the interrupter, an adjustable'plate selectively secured in either of two positions on opposite sides of said housing, said housing having elongated slots in opposite sides thereof and said plate having means adjustably and selectively extending through 'any of said slots in cooperation with said actuating means for setting the edge distance of the magneto in either direction of rotation, and a cover pl'ate secured to said hous ing over the slots at the side of the housing opposite from that on which is selectively secured the adjustable plate.

8. In a magneto, a mechanical interrupter, means for actuating the interrupter, a housing for the interrupter, an adjustable plate secured in adjusted position on the housing for setting the edge distance of the magneto, and means for rendering the adjustable plate dlflicult to read ustment.

In witness whereof we aflix our signatures.

O. AUGUST MAYER. ADOLPH ROSNER. 

